Daniel higham



(No Model.) D. HIGHAM.

REGULATION OF ELECTRIC GENERATORS.

No. 374,406. Patented Dec. 6, 1887.

N. PETERS. Plwloulhn n hcr. Washington. D. C.

UNITED, STATES PATENT OFFICE.

DANIEL HIGHAM, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR TO THE HIGHAlVIELECTRIC MOTOR COMPANY, OF SAME PLACE.

REGULATION OF ELECTRIC GENERATORS.

SPECIFICATION forming part of Letters Patent No. 374,406, dated December6, 18 87.

(-No model.)

vfor the automatic regulation of electric generators for the productionof a constant current in circuits of varying resistances, due totranslating devices which are switched into and out of the circuits.v

In the accompanying drawings, Figure 1 is a diagram illustrating oneform of my invention, which is intended for the larger sizes ofgenerators. Fig. 2 is a diagram illustrating another form,whichisintended for the smaller sizes of machines, and Fig. 3 is a diagram ofa modification.

Inthe construction shown in Fig. 1 the magnets F are wound with two setsof coils, one opposing the action of the other. The coils f, which arein a shunt-circuit around the armature, are the main energizing-coils,while the coils c, which are the regulatingcoils, are connected inseries with the armature-coils in the working-circuit.

From the brush a extends a conductor, 8, with which is arranged to makecontact an arm or armature-lever, 6, connected to the lead 19. Anelectro-magnet, E, whose coils arein the working-circuit, controls thisarmaturelever. When this armature'lcver e is not attracted by theelectro-magnet, a shuntcircuit will be closed around the opposing coils,which are thus cut out of action.

When the current in the working-circuit rises above the predeterminedstrength, the

electro-magnet E will throw the opposing coils 0 into action byattracting the armaturelever e and breaking the contact at t, therebyreducing the magnetic intensity of the fieldmagnets. When the magneticfield becomes so reduced as to reduce the current in the working circuitbelow the predetermined strength, the armature-lever e of theelectromagnet E will be drawn by the retractingspring 00 to make contactat 15, whereby the opposing coils 0 will be cut out through theshort 5ocircuit of the conductor 3. The magnetic field then being increasedagain, the current will come up toits normal strengtlnwhereitisin thismanner maintained constant.

In order that the current generated shall 5 5 not be pulsatory, theelectromagnetic circuitbreaker above described should be so sensitivethat the smallest appreciable variation in the working-current would becapable of effecting regulation. The cont-act at t will then be s0rapidly made and broken thatthe current will be practically continuous.The number of ampere turns in the opposing coils should be such that thefull current therein would so reduce the magnetic effect of theshunt-coils that the current of the shunt-coils could not producesufficient potential at the terminals of the armature (when running atthe working speed) to sustain the current of the shunt-coils against theresistance of the shunt-circuit. Under these conditions theelectromagnetic circuit-breaker will be capable of maintaining thecurrent constant with any resistance in the working-circuit up to itsmaximum resistance. 7 5

In the construction shown in the diagram, Fig. 2, the current ismaintained constant in substantially the same manner; but in this case,instead of employing opposing coils on the field-magnet, I put all thecoils f in series and provide for throwing the entire field-magnet coilsinto and out of action by means of the electromagnetic circuit-breaker;but as these coils are the energizing-coils, and not opposing ones, thecontact t is placed on the opposite side of the armature e from thatshown in Fig. 1. It is not always necessary, however, that the entirefield-magnet coils should be cut out. For instance, in cases where thetrans lating devices are never all at one time cutout 0 of the circuitsa portion only of the fieldinagnet coils need be short'circuited, asindicated in Fig. 3, so long as the magnetic field will be reducedsufficiently to check an excess of current when that portion of thecoils is 5 cut out.

I claim as niy invention- In testimony whereofl have signed my name Anelectric generator having its field-inagto this specification in thepresence of two subnet coils and armature-coils in series in the yscribing witnesses. Working-circuit, in combination with a short DANIELHlGl-IAM. circuit around said series, field-magnet coils, \Vitnesses:and an electromagnetic circuit-breaker in the WILLIAM D. CONNER,working-circuit to close the said short circuit. I HARRY SMITH.

